A Longitudinal Analysis of the Impact of Physical Activity on Neurocognitive Functioning Among HIV-Infected Adults

  • Catherine A. Dufour
  • María J. Marquine
  • Pariya L. Fazeli
  • Anya Umlauf
  • Brook L. Henry
  • Zvinka Zlatar
  • Jessica L. Montoya
  • Ronald J. Ellis
  • Igor Grant
  • David J. Moore
  • HIV Neurobehavioral Research Program Group
Original Paper

Abstract

Higher levels of physical activity (PA) have been linked to better neurocognitive functioning in many populations. The current study examines the longitudinal association between PA and neurocognitive functioning among HIV-infected and HIV-uninfected persons. Community-dwelling adults (N = 291) self-reported level of PA and completed a comprehensive neuropsychological battery at two to four study visits (Mean follow-up time = 2.6 years). Participants were divided into three PA groups: “No PA” (no PA at any visit), “consistent PA” (PA at ≥50% of visits), and “inconsistent PA” (PA < 50% of visits). A mixed effect model, adjusting for significant covariates showed that all PA groups had statistically significant, yet modest, neurocognitive decline over time; and, the consistent PA group began with, and maintained, significantly better neurocognitive function compared to the other two PA groups. This effect was evident among both HIV-uninfected and HIV-infected persons, despite the fact that HIV-infected persons showed lower baseline neurocognitive function. PA is a modifiable lifestyle behavior that may help to protect against neurocognitive impairment regardless of HIV status, however, given the proportion of HIV-infected individuals who evidence neurocognitive difficulties, a focus on increasing PA seems warranted.

Keywords

HIV/AIDS Cognition Physical activity Exercise Neurocognitive impairment HIV-associated neurocognitive disorders 

Resumen

La actividad física (AF) ha sido asociada con un mejor funcionamiento neurocognitivo en varios grupos. Este estudio examinó la asociación longitudinal entre la AF y el funcionamiento neurocognitivo en personas con y sin infección del VIH. Adultos viviendo en la comunidad (N = 291) proporcionaron información acerca de sus niveles de AF y completaron una batería neuropsicológica exhaustiva. Los participantes completaron entre dos y cuatro visitas relacionadas con el estudio (tiempo de seguimiento promedio = 2,6 años) y fueron divididos en tres grupos de AF: “Ninguna AF” (Ninguna AF durante todas las visitas del estudio), “AF Consistente” (AF durante 50% o más de las visitas del estudio), y “AF Inconsistente” (AF durante menos del 50% de las visitas del estudio). Un modelo estadístico mixto, ajustando por el efecto de variables externas, indicó que hubo una reducción estadísticamente significativa, pero poco pronunciada, en el funcionamiento neurocognitivo en todos los grupos. Además, el grupo con AF Consistente demostró un mejor funcionamiento neurocognitivo en comparación con los otros dos grupos de AF al comienzo del estudio, el cual se mantuvo durante el seguimiento. A pesar de que las personas con VIH demostraron un funcionamiento neurocognitivo más bajo al comienzo del estudio que las personas sin VIH, el efecto de AF fue demostrado en los dos grupos. Es importante recalcar que la AF es un factor de vida modificable que podría proteger contra los daños neurocognitivos independientemente de si las personas tienen o no VIH. Dada la proporción de personas con VIH que demuestran problemas neurocognitivos relacionados con esta enfermedad, será importante enfocar los esfuerzos investigativos en desarrollar formas de incrementar la AF en este grupo de personas.

Notes

Acknowledgements

The San Diego HIV Neurobehavioral Research Program group is affiliated with the University of California, San Diego, the Naval Hospital, San Diego, and the Veterans Affairs San Diego Healthcare System, and includes: Director: Robert K. Heaton, Ph.D., Co-Director: Igor Grant, M.D.; Associate Directors: J. Hampton Atkinson, M.D., Ronald J. Ellis, M.D., Ph.D., and Scott Letendre, M.D.; Center Manager: Thomas D. Marcotte, Ph.D.; Jennifer Marquie-Beck, M.P.H.; Melanie Sherman; Neuromedical Component: Ronald J. Ellis, M.D., Ph.D. (P.I.), Scott Letendre, M.D., J. Allen McCutchan, M.D., Brookie Best, Pharm.D., Rachel Schrier, Ph.D., Terry Alexander, R.N., Debra Rosario, M.P.H.; Neurobehavioral Component: Robert K. Heaton, Ph.D. (P.I.), J. Hampton Atkinson, M.D., Steven Paul Woods, Psy.D., Thomas D. Marcotte, Ph.D., Mariana Cherner, Ph.D., David J. Moore, Ph.D., Matthew Dawson; Neuroimaging Component: Christine Fennema-Notestine, Ph.D. (P.I.), Terry Jernigan, Ph.D., Monte S. Buchsbaum, M.D., John Hesselink, M.D., Sarah L. Archibald, M.A., Gregory Brown, Ph.D., Richard Buxton, Ph.D., Anders Dale, Ph.D., Thomas Liu, Ph.D.; Neurobiology Component: Eliezer Masliah, M.D. (P.I.), Cristian Achim, M.D., Ph.D., Ian Everall, FRCPsych., FRCPath., Ph.D.; Neurovirology Component: David M. Smith, M.D. (P.I.), Douglas Richman, M.D.; International Component: J. Allen McCutchan, M.D., (P.I.), Mariana Cherner, Ph.D.; Developmental Component: Cristian Achim, M.D., Ph.D.; (P.I.), Stuart Lipton, M.D., Ph.D.; Participant Accrual and Retention Unit: J. Hampton Atkinson, M.D. (P.I.), Jennifer Marquie-Beck, M.P.H.; Data Management and Information Systems Unit: Anthony C. Gamst, Ph.D. (P.I.), Clint Cushman; Statistics Unit: Ian Abramson, Ph.D. (P.I.), Florin Vaida, Ph.D. (Co-PI), Reena Deutsch, Ph.D., Anya Umlauf, M.S., Christi Kao, M.S.

Disclaimer

The views expressed herein are those of the authors and do not reflect the official policy or position of the US government.

Compliance with Ethical Standards

Funding/Support

The following NIH Grants provided funding for the current work: P30MH062512 and P01DA012065. Dr. Marquine is funded by K23MH105297. Dr. Fazeli is funded by K99/R00 AG048762. Dr. Zlatar is funded by K23 AG049906.

Financial Disclosure

Catherine A. Dufour declares that she has no conflict of interest. María J. Marquine declares that she has no conflict of interest. Pariya L. Fazeli declares that she has no conflict of interest. Anya Umlauf declares that she has no conflict of interest. Brook L. Henry declares that he has no conflict of interest. Zvinka Zlatar declares that she has no conflict of interest. Jessica L. Montoya declares that she has no conflict of interest. Ronald J. Ellis declares that he has no conflict of interest. Igor Grant declares that he has no conflict of interest. David J. Moore declares that he has no conflict of interest.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the University of California, San Diego, and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Informed consent

Informed consent was obtained from all individual participants included in the study.

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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • Catherine A. Dufour
    • 1
  • María J. Marquine
    • 1
  • Pariya L. Fazeli
    • 1
  • Anya Umlauf
    • 1
  • Brook L. Henry
    • 1
  • Zvinka Zlatar
    • 1
  • Jessica L. Montoya
    • 1
    • 3
  • Ronald J. Ellis
    • 1
    • 2
  • Igor Grant
    • 1
  • David J. Moore
    • 1
  • HIV Neurobehavioral Research Program Group
  1. 1.Department of Psychiatry, HIV Neurobehavioral Research CenterUniversity of CaliforniaSan DiegoUSA
  2. 2.Department of NeurosciencesUniversity of CaliforniaSan DiegoUSA
  3. 3.SDSU/UCSD joint Doctoral Program in Clinical PsychologySan DiegoUSA

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